Cooling system



July 9, 1935.

S. M. ANDERSON COOLING SYSTEM Original Filed Jan. 51, 1934 4 2Sheets-Sheet l flarfiuebm. (21712671901;

July 9, 1935. sfM. ANDERSON 2,007,291

COOLING SYSTEM Original Filed Jan. 31, 1934 2 Sheets-Sheet 2 IzzvckziarJamaal 77a azzdersozz Patented July 9, 1935 COOLING SYSTEM Samuel M.Anderson, Sharon, Mass., assignor to RF. Sturtevant Company, Inc.,Boston, Mass.

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tems- Original application January 31, 1934, Serial No.

709,118. Divided and this application January 12, 1935, Serial No. 1,524

2 Claims.

This invention relates to the conditioning of air for passengervehicles, and relates more particularly to the conditioning of aircirculated through railway cars.

This application is a division of my co-pending application, Serial No.709,118, filed January 31,

It is now becoming well known that human comfort requires that the airwithin an enclosure should be not only circulated to provide sufiicientventilation, but should in winter be warmed, with moisture added tomaintain the proper relative humidity, and in summer should be cooled,and moisture extracted from it to overcome the excessive humidity whichis usually present.

While the conditioning of air for motion picture theaters, hotel, officeand industrial buildings has been developed to a high degree in recentyears, the air conditioning of vehicles, and particularly railway cars,has been more or less neglected, due, perhaps, to the peculiar problemsinvolved and the many difliculties present. Among the difliculties whichpresent themselves are the lack of space'in a railway car, which alreadyof necessity has had to accommodate the maximum of equipment in theminimum of space,

,Y the excessive refrigeration equipment which would have to be carriedit the ordinary method of conditioning buildings were followed, thechanging temperature conditions through which a railway car must pass,the cost of the equipment, and other difliculties.

According to a feature of this invention, an air conditioning system inwhich the conditioned air is distributed without ducts, is provided. Theair conditioning chamber is mounted in the center of the car, or otherspace being served, and the conditioned air is discharged towards eachend of the car from the center. The air is discharged from the chamberin two loop circuits, overhead the passenger space. The air passes downalong one side of the car and overhead the passenger space and isreturned to the chamber down along the other side of the car andoverhead the passenger space from each of the two sides of the chamber,the chamber thus serving to supply air without ducts from a centrallocation to the two halves of the car. is drawn into the chamber,filtered, temperature conditioned, and discharged. In summer, the air iscooled and dehumidified, and, in winter, the air is heated andhumidified.

According to another feature of the invention, the compartment issupplied with cold water from the ice cooling system andpre-coolingcoils are Outside and recirculated air provided in the pathof mixed outside and recirculated air, the warmest ice water being fedthrough the pre-cooling coils which extract all of the heat possiblefrom the air being conditioned.

An object of the invention is to provide precooling coils in an icecooling system in the path of the mixed recirculated and outside air tobe conditioned.

Other objects of the invention willbe apparent from the followingdescription taken with the drawings.

The invention will now be described with reference to the drawings, ofwhich:

Fig. 1 is a side view of a railway car equipped according to the presentinvention;

Fig. 2 is a plan view, with top removed, of the car and apparatus ofFig. 1;

Fig. 3 is a view looking into the car of Figs. 1 and 2 from one end,with end removed;

Fig. 4 is a diagrammatic view showing an ice cooling system for coolingthe air;

Fig. 5 is a sectional plan view showing the apparatus in an airconditioning chamber of this invention, and

Fig. 6 is a side sectional view of the compartment shown by Fig. 5.

The air conditioning compartment shown by Fig. 6 comprises an insulatingcasing III which extends completely around the sides of the compartment.The compartment contains the extended surface main cooling coils II, theprecooling coils I2, the steam heating coils I3, the steam humidifiersI4, the fans I5, which are driven by motor I6 through the intermediaryof the belt I1, the outside air inlets I8, the filters I8 mounted withinthe inlets IE on the inside of the compartment, the recirculated airinlets 20, and the discharge outlets 2|.

The cooling compartment is thus seen to have two recirculated air inletsand two discharge butlets. The compartment is divided into two units bythe partition 22 so that the air drawn in by one of the fans I 5 entersthrough one of the outside air inlets I8, one of the recirculated airinlets 20, passes first over one of the pre-cooiing coils I2, then overhalf of the cooling coils II, then over the steam coil I3, and out oneof the discharge outlets 2 I. It is seen thattwo complete units, eachserving half of the car with conditioned air, are provided in a singlecompact and eflicient compartment requiring a minimum of apparatus dueto the fact that much of the apparatus is common to the two units.

The air is discharged, as shown by Figs. 1 and 2,

overhead the passenger space and down along one side of the car, and isreturned overhead the passenger space and down along the other side ofthe car. It has been found that this arrangement 5 is particularlysuitable for the supply of cold and dehumidified air in hot weather. Inorder to dehumidify the air sufliciently, it is usually necessary tocool it to a very low dew point, at which the temperature of the coldair is too low for comfort. But, with the present arrangement, thishighly cooled air does not enter directly the area occupied bypassengers. Air is circulated completely above the passenger space, and,by the action of gravity, the cold air gradually diffuses down from thelevel at which it is discharged from the cooling compartment, and,before entering the area occupied by passengers, contacts intimatelywith the warm air above the passenger space and so has sufilcientsuperheat added to it by the time the conditioned air reaches thepassengers it has a temperature which is not too cold for comfort.

An ice cooling system such as that illustrated by Fig. 4 may be used forcooling the car. In this case, ice water is circulated through thecooling coils H by the pump 25a, the returned water being sprayedthrough the spray nozzles 26 on the ice surface so as to remove, by themelting ;of the ice, the heat units in the water. In order to preventthe excess water caused by the melting of the ice from being dischargedto the tracks at too low a temperature, a portion of the rela tivelywarm water leaving the cooling coils II is passed at the junction point28 (Fig. 5) through the two pre-cooling coils I2, one of which ismounted in each of the two air conditioning units included within thecooling compartment ll.

. The amount of water passing through the precooling coils I2 ispreferably equal to that which would ordinarily be excess water, causedby the melting of the ice, and ordinarily drained to the tracks. Thiswater serves to additionally cool the air and then is discharged fromthe cooling coils l2, through the pipe 30a, to the compartment 21, fromwhich it is drained to the tracks.

It has been the practice in the past to mount pre-cooling coils, such ascoils If, in the outside air inlets. The advantages of mounting coils inthe path of the mixed outside and recirculated air are that less poweris required to move the air over the coils to obtain the same heattransfer. Usually the larger part of the conditioned air is recirculatedair, while a minor portion'is outside air. To obtain suflicient heattransfer from a pre-cooler used to cool the small volume of outside airrequires more surface in a smaller area with higher resistance thanwhere the pre-cooler is mounted in the path of the mixed air, where, dueto the larger volume, less surface is required. Also, from the designengineering standpoint, it is preferable that all of the heat exchangesurfaces be arranged within the main cooling compartment where morespace is available.

Whereas the invention has been described in connection with theconditioning of air supplied to passengers within a railway car, itshould be understood that the invention is also applicable to any otherenclosure to which it is desired to supply conditioned air.

Whereas one embodiment of the invention has been described for thepurpose of illustration, it should be understood that the invention isnot limited to the details described, since mam! modifications may bemade by those skilled in the art without departing from the spirit ofthe invention.

What is claimed is:

1. Air conditioning apparatus for a passenger vehicle, comprising aconditioning compartment located in the roof zone of the vehicle, meansfor drawing in fresh and recirculated air and passing it through saidcompartment, air cooling means in said compartment, an ice chamber forproviding cold water through the melting of ice, means for circulatingthe cold water to said cooling coil and returning a portion of same tosaid chamber, a pre-cooling coil mounted in said compartment in the pathof the mixed outside and recirculated air, and means for continuouslypassing the remaining portion of the cooling water leaving said coolingcoil through said pre-cooling coil and then discharging it from saidvehicle.

2. Air conditioning apparatus for a passenger vehicle, comprising aconditioning compartment located substantially in the center of thevehicle and in the root zone thereof, completely above the usefulpassenger space, a cooling coil in said compartment, means for drawingair in fresh and recirculated air and passing it over said coil, an icechamber for cooling water through the melting of ice, means forcirculating the cold water through said coil and for returning aportion'of same to said chamber, a pre-cooling coil, and means forcontinuously passing the other portion of the water leaving said coolingcoil and then discharging it from said vehicle through said precoolingcoil.

SAMUEL M. ANDERSON.

